• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.426-433
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• 1986

This experiment was carried out to investigate the competitive ability and the interaction of each species in ten mono-and binary-associations of four forage species; orchardgrass, tall fescus, ladino clover, and alfalfa. Each species was grown in intra- and interspecific stands in large pots for one year. And samplings of shoot and root were taken in Spring, Summer, and fall clipping stages. Intra- and interspecific competition was compared and evaluated by expected yield, aggressivity, relative yield total(RYT), compensation index(CI), general combining ability(GCA), and specific combining ability (SCA) with shoot and root dry matter production of each species in monoculture and binary mixture. The forage yield was high in two grass species and the mixture of them, but low in two legume species and the mixture of them. The mixture of tall fescue-ladino clover was evaluated as a productive association with a high PYT(1.05) and a high SCA(0.79), and tall fescue was a more aggressive species in it. Each of grass-grass and legume-legume mixture was less aggressive between two species and lower SCAs than grass-legume mixtures. Especially, orchardgrass was the most agressive species and alfalfa was the least, but tall fescue had the highest GCA and ladino clover had the lowest in shoot competition. Also in root, tall fescue- ladino clover mixture was a good match with a high RYT(l.12) and a high SCA (0.60), and orchardgrass was highest in aggressivity. However, orchardgrass had the highest GCA in root while tall fescue had the highest in shoot.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.9
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• pp.914-923
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• 2009

Helix antennas have been widely applied to satellite TT&C, data communication and GPS receiver systems onboard military, remote sensing and communication purpose satellites. The helix antennas are known to be convenient to control impedance and radiation coverage characteristics with a maximum directivity in satellite z-axis. Waveguide horn is commonly used for radar system that needs ultra-wideband pulse for exploration ground radar and electromagnetic disability measurement etc. It has high efficiency and low reflection characteristics provided by the low-profile shape and suppressed radiation distortion. In this paper, a waveguide horn structure incorporated with helix antenna design is proposed for satellite applications that require ultra-wideband pulse radar and high rate RF data communication link to ground station over wide coverage area. The main design concern is to synthesize variable beam forming pattern based on modified horn-helix combination helicone structure such that multi-mission antenna is implemented applicable for TT&C, earth observation, high data rate transmission. Waveguide horn helps to reduce the overall antenna structure size by introduction fold type reflector connected to the tapered helix antenna. The next generation KOMPSAT satellite currently under development requires high-performance precision attitude control system. We present an initial design of a hybrid hern-helix antenna structure suitable for efficient RF communication module design of multi-purpose satellite systems.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.1
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• pp.31-36
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• 2002

The yield and quality of winter forage crops such as oats could increase by mixed sowing with a winter legume such as hairy vetch(Vicia villosa Roth). The purpose of this study was to improve the forage quality and productivity using Oat-Hairy vetch mixture in winter season for three years. The results of this experiments were summarized as follows. In mix seeding of oat and hairy vetch, the dry matter(DM) content of herbage was 15∼16% in fall-harvest and 19∼20% in spring-harvest. Crude protein(CP) content of hairy vetch was the highest as 30.1% and the mixture was higher than that of oat. Acid detergent fiber(ADF) and neutral detergent fiber(NDF) content of hairy vetch was lower, but in vitro dry matter digestibility(IVDMD) and total dry matter digestibility(TDN) content was higher than that of oat. Although oat showed the low yield by 3.7∼4.4 DM t/ha, the Fall-seeded-Spring-harvest hairy vetch plot showed highly production by 9.5 DM t/ha. Crude protein and TDN yield of Fall-seeded-Spring-harvest plots were higher than those of others. According to this study, the highest dry matter yield could be obtained by Fall-seeded-Spring-harvest. It would be recommend in cropping field for oat.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.719-729
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• 2018

Green manure crops can be efficient replacements of high nutrient materials such as livestock compost, organic fertilizers, etc. in organic farming. Grass-legume mixtures or mixed cropping of legumes with non-legumes can aid in abating the shortcomings of each plant type under monoculture (i.e. legumes have low biomass yields while grasses are poor at fixing nitrogen). This study was conducted to investigate the effects of barley (B) and hairy vetch (H) mixtures on green manure yield in nutrient accumulated organic upland soils of Korea. In one cropping season, single crops of barley and hairy vetch (Barley: 160 kg/ha, Hairy vetch: 90 kg/ha) as well as mixtures of both crops at different seeding rates (B66:H33, B33: H66) were grown and the obtained results are as shown below. The biomass yield and nutrient productivities were higher in barley-hairy vetch mixture. The biomass yield and total phosphorus content were higher for the mixed crops by 78~132% and 200% respectively than those of the hairy vetch monoculture. Total nitrogen content of the mixed crops was also higher than those of the barley monoculture by 43~44%. The biomass yield (5.60 Mg/ha) and nutrient contents (87.7 kg N/ha, 23 kg $P_2O_5/ha$) were highest in the case of B66:H33 seeding rate. Accordingly, this study concludes that the barley-hairy vetch mixtures cropped at B66:H33 seeding rate is efficient in increasing green manure productivity due to complementary effects observed and the highest biomass yield and nutrient contents.

• The Korean Journal of Rheology
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• v.2 no.2
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• pp.28-34
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• 1990

최근 고분자 산업의 발달과 함께 고분자 혼합공정에 대한연구와 더불어 internal 혼 합기에 대한 관심이 고조되어 왔다. 본문에서는 효율적인 로우터 고안을 위하여 수학적 모 델을 이용하는 computer aided design을 다루었다. Computer aided design 하기 위하여 고 려된 인자는 유변학적 성질, 작업조건, 로우터의 형상이었으며 고안된 혼합기의 평가는 로우 터 날에서의 응력과 순환시간을 사용하였다.

• 프린팅코리아
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• s.18
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• pp.132-137
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• 2003

최근 윤형두 범우사 대표가 '옛책의 한글판본'을 펴냈다. 윤형두 대표는 머리글에서 "한글은 우리민족의 가장 소중한 문화유산이다. 이제 우리는 더욱 한글을 아끼고 갈고 닦지 않으면 녹슬고 곰피어 우리의 혼이 빼앗기고 말 것이다. 한글사랑은 곧 나라사랑이다. 이런 생각으로 옛책의 한글본을 엮어보았다"라고 말했다. 이 책은 훈미정음을 시작으로 경신록언석까지 36종의 옛책을 소개하고 있다. 본지에서는 2회에 걸쳐 소개한다.

• 주택과사람들
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• s.193
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• pp.98-103
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• 2006

최근 이스탄불의 골든혼 해협에서 보스포러스 해협으로 이어지는 신시가지의 부동산 시장이 초강세를 보이고 있다. 2005년 10월에 시작된 유럽연합 가입 협상을 계기로 터기의 부동산 시장이 본격적인 상승 탄력을 받으며 세계의 주목을 받기 시작한 것. 보스포러스 해협 주변에는 고급주택 및 신축 붐이 일고 있고 고층 아파트 위주로 가격이 상승하고 있는 이스탄불의 주택 시장을 직접 취재했다.

• Magazine of RCR
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• v.6 no.1
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• pp.22-27
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• 2011

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1149-1150
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• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.749-750
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• 2013